CEV & CLV moving target

[gunsandrockets]

Ed, I'm shocked you actually posted the correct numbers for the Apollo volume. Probably because you also mischaracterized the volume as the same as a coffin.

 

[gunsandrockets]

gofer, I like astronautx.com very much and use it a lot. He does get some details incorrect from time to time, probably a function of just how huge the site is.<br /><br />The numbers for the 5.5m CEV crew module, according to the NASA ESAS report, are 9.5 tonnes mass and three times the pressurized volume of the Apollo capsule. If we multiply the Apollo living volume of 6.2 cubic meters we get 18.6 cubic meters for the CEV capsule.<br /><br />The astronautix numbers for the Big Gemini reentry vehicle are 5.2 tonnes mass and 18.7 cubic meters of living space.<br /><br />According to these numbers the volume of the Big Gemini capsule is almost identical to the CEV capsule, but the Big Gemini capsule is 45% lighter than the CEV capsule. That's a surprise.<br /><br />Even taking into account the heavier heat shield of the CEV capsule the difference in mass shouldn't be that great. I suspect the Big Gemini mass may be optimistically too low and/or the CEV mass pessimistically too high. Unlike the stainless steel structure of the Apollo capsule, the CEV capsule will make use of modern composites in the structure and modern lighweight thermal protection for the forebody. Even with the lightweight titanium structure of the Gemini I can't see how the Gemini manages a mass advantage of 45% over the CEV.

 

[radarredux]

> <i><font color="yellow">My complaint is not that the ESAS plan is completely wrong, I merely protest against anyone who waves around the ESAS report as the final word on the topic, in a transparent attempt to shut down debate.</font>/i><br /><br />I think NASA's actions agree with your position that ESAS is modifiable, especially since a number of elements of the original design have already been changed (e.g., the methane engine, the SSME for the CLV upper stage and CaLV, the diameter of the CaLV).<br /><br />Reminds me of a quote (I first heard it from Bill Gates): "<i>I would rather be right than consistent.</i>"</i>